Debian is a Linux distribution, that's preffered for desktop computers, yet it has been becoming more popular as a server Operating System over the last few years as well. It is really stable and secure, since fixes are released in a couple of days after a problem is discovered. Debian has a huge support community, so if you have any questions or troubles with the OS or with some of the 30,000+ packages it features, you are able to contact the developers immediately through electronic mail using special e-mail lists and receive a reply within 15-20 minutes. The Debian community provides the top level of support possible, as all of your questions will be handled by exactly the same people who built Debian in the first place, so they have an in-depth knowledge of how their own system functions. Since the Operating System is absolutely free to use and distribute, no license charges will be included with your web hosting fees and you will be able to customize the code files and any other software that you install without restrictions, so as to optimize the software environment for your websites. In addition, Debian performs really well on any kind of hardware, because it's light and effective and doesn't require a lot of memory.